1. Field of the Invention
The present invention relates generally to ocular surgery, and more specifically to an intraocular lens (IOL) insertion systems.
2. Description of the Related Art
Phacoemulsification surgery has been successfully employed in the treatment of certain ocular problems, such as cataracts, and typically entails removing a cataract-damaged lens and implanting an intraocular lens, or IOL. Phacoemulsification surgery involves removal of the cataract damaged lens utilizing a small incision at the edge of the cornea. Through the small incision, the surgeon creates an opening in the capsule, i.e. membrane that encapsulates the lens, and can through the opening can remove unwanted lens material and insert an IOL.
IOLs typically include a haptic or haptics, namely devices used to hold the lens in place. Current techniques for fabricating IOLs employ deformable polymeric materials such as acrylic, silicon, hydrogel based materials, and the like. For example, Abbott Medical Optics (AMO) of Santa Ana, Calif. manufactures a brand of aspheric IOL using a single piece of acrylic material called Tecnis®.
When performing phacoemulsification surgical techniques, such as lens insertion, the deformable polymeric materials enable the surgeon to fold, roll, and otherwise configure the IOL in a manner sufficient to position and orient the lens for placement within an eye. Once positioned and oriented, the surgeon may manually deliver the configured lens from an insertion cartridge device into an injector device and ultimately to the eye through a small incision. In general, the insertion cartridge device is installed within an IOL insertion system, i.e. a separate delivery handpiece. The surgeon may introduce the IOL manually using the IOL delivery handpiece, such as through a delivery tube, in a manner similar to operating a hypodermic needle. The IOL injector device arrangement moves the IOL from a holding area, specifically a cartridge device, located within the injector. In this arrangement, the IOL is ready for implantation, and the surgeon may engage the insertion system injector device plunger component to push the IOL into the patient's eye.
The injector device may involve a preloaded injector or a reusable, limited reuse injector, or an injector configured with an IOL insertion cartridge, arranged to ensure successful ejection and unfolding of the IOL and for protecting the integrated rear or trailing haptic sufficient to prevent damage to IOL and the haptic.
The material properties of flexible acrylic IOLs are highly dependent on the size of the insertion cartridge and the ability of a surgeon to provide the precise pressure or force necessary to insert the IOL. Use of an injector device in this manner may make it easier for the surgeon to fold and manipulate the IOL and deliver the IOL through a small cartridge and through the incision while protecting the integrity of the haptics.
Haptics may include leading and trailing haptics, where the leading haptic is the first haptic inserted through the incision and the trailing haptic the second haptic passing through the incision. This may be realized through a small slit in the IOL holding area or insertion cartridge device prior to engaging the plunger to push the IOL and move the IOL from the injector for implantation into the patient's eye.
Current methods and designs may become problematic during ejection, when the IOL unfolds from the cartridge device/holding area. During this stage of the optical procedure, the IOL and/or the integrated leading and/or trailing haptics may become damaged. Trailing haptic damage is of particular concern due to the generally increased likelihood of such damage relative to damage to other parts of the IOL. Also, current designs may fail to properly manage the forces required to move the IOL from the holding area and through the injector during insertion.
Based on the foregoing, it would be beneficial to offer a single handpiece design for operating a manual IOL insertion system configured for dynamic control of the insertion force while maintaining control of the haptic/lens configuration, where the surgeon may complete the lens replacement procedure without damaging the IOL or integrated haptics during the insertion process.